Work positioner

ABSTRACT

A remote work positioning and measuring apparatus adapted to be mounted on a variety of stock handling machines. A slidable work engaging carriage is moved along the working surface by a hand crank. A tape measure extends between the slidable carriage and the frame of the machine, being wound onto spring-loaded reels at both ends. A hand crank allows the tape to be shifted from one reel to another unless an electromagnetic lock is activated to lock the tape with respect to the movable carriage.

United States Patent Gundersen 451 July 25, 1972 541 WORK POSITIONER3,180,029 4/1965 Perwas ..33/170 [72] Inventor: Ralph w Gundemn, St PaulMinn. 2,353,726 7/1944 Guttman ..33/l 25 R [73] Assignee: Power DriveCorporation, St. Paul Park, P ima y Examiner-Robert B. Hull MinAttorney-Robert M. Dunning [2 H Appl' 107064 A remote work positioningand measuring apparatus adapted to be mounted on a variety of stockhandling machines. A 521 u.s.c| ..33/|2s 33/138 slidable Work engagingcarriage is [51] Int CL i h 6 3/10 surface by a hand crank. A tapemeasure extends between the 581 Field of Search ..33/125 I38 SlidableCarriage and the frame machine being Wmmd onto spring-loaded reels atboth ends. A hand crank allows the [56] References Cited tape to beshifted from one reel to another unless an electromagnetic lock isactivated to lock the tape with respect to UNITED STATES PATENTS themovable carriage 2,728,143 12/1955 Buchet ..33/l38 10 Claims, 2 DrawingFigures mmmmsmz L. "uh. W18

III I HI I 1 Elm ll/flljlllllllll|lllllll|llll lluj b ll INVENTOR RALPHW GUNDERSE/V GYM \ 9mm ATTORNEYVGM WORK POSITIONER BACKGROUND OF THEINVENTION In the prior art, machines for cutting and punching largepieces of metal, wood, and the like have generally been clumsy, slow,and required two or more people to operate. The reason for this is that,in order to position the piece of stock being worked, at least two menwould have to stretch a tape measure out to the desired length, positionthe stock on the working surface, and measure the correct distancesbefore the tool operation could be performed. There is accordingly adefinite need in the art for a self-contained work positioning apparatusthat will permit one man to perform these tasks while remaining near theparticular tool being used. My invention provides such a machineallowing a single operator to position a piece of stock under a tool inseveral different exact locations, move the stock, and measure the stockall from a single location.

SUMMARY OF THE INVENTION Briefly, my-invention contemplates a slidablestock engaging carriagewhich is clamped to one end of the particularpiece of stock being worked. The carriage is moved back and forth alongthe guide track by means of a hand crank located near the tool end ofthe machine. Two spring-loaded tape reels are employed, one mountedproximate the tool end of the machine and the other mounted on thesliding carriage. A tape measure is wound between the two reels in sucha manner that the. spring tensions of the reels oppose each other.Another hand crank near the tool is used to shift the tape measure ofiof one reel onto the other reel so that the zero mark on the therefore,be seen that it is an object of my invention to supply a remote workpositioning and measuring machine operable by one person. Furtherobjects and advantages will become apparent from the followingdescription and drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a schematic top view of themajor components of my invention.

FIG. 2 is a schematic side view of the major components of my invention.Both figures are shown with the protective housings in section so as topermit a clear view of the components inside.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention isdesigned to work with a wide variety of tools including hydraulicpunches, drills, saws, .and the like. Normally these tools employ a longtable extending off, to one side upon which rests the piece of metaltube or angle or other piece of stock upon which work is to beperformed, In the past the stock has usually been moved on the table byhand into position under the tool and measurements have been made byhand. My invention, on the contrary, employs a sliding carriage assemblywhich follows a track along side the table and engages the stock bymeans of a suitable clamp or clamps well known to those skilled in theart. Referring simultaneously to FIGS. 1 and 2 this track is shownschematically as a track 10. The carriage assembly is shown generally bythe numeral 12 and rides on track by means of a sliding bearing 14 of atype commonly available in the art designed to follow track 10. Carriagel2'comprises a housing 16 welded to a connecting member 18 which in turnis bolted to a flange 20 which is mounted on the top of bearing 14. The

workingtable is generally above the carriage assembly .12 in theposition shown by a small cut-away working table portion 22 in FIG. 2. Awork engaging extension bracket 24 is mounted to member 18 and extendsupward either beside or through a slot in the table surface 22. Althoughnot shown in the drawing a clamp of any convenient design is welded orbolted to the top of bracket 24in a position suitable to engage whateverpiece of stock is being worked on top of the table. Consequently, ascarriage assembly 12 movesback and forth along guide track 10, extensionbracket 24 and the clamp thereon engage the stock on table surface 22and move it back and forth accordingly. It can be seen in the drawingsthat the carriage is remotely movable from the tool end of the machineby a hand crank 26 which is mounted in a fixed housing 28. A shaft 29from hand crank 26 extends: through housing 28 to a sprocket 30. Aroller chain 32 on sprocket 30 extends along track 10 to connect with abracket 34 on the bottom of bearing 14. The opposite end of chain 32 isnot shown in the drawings since the total length of the machine cannotbe included in the limited space of the drawing. Chain 32, however,travels over a suitable idler sprocket at its far end and returns tosprocket 30. A brake 38 is provided on shaft 29 so as to allow thecarriage to be locked in any predetermined position. For a more detailedexplanation of a brake and chain arrangement such as described here,reference should be had to my co-pending application for RemoteMeasuring Apparatus Ser. No. 76,052 filed Sept. 28, 1970 by the instantinventor.

The improvement contemplated by my invention resides in providing twospring-wound tape reels 40 and 42 positioned respectively in fixedhousing 28 and on sliding carriage assembly 12 in housing 16. Extendingbetween reels 40 and 42 is a metal tape measure 44 which passes over aset of idler wheels 46, 47 and 48. Reel 40 is connected to a springchamber 41 containing a spiral spring connected to urge rotationalmotion on reel 40 in a direction so as to wind up tape measure 44. In asimilar manner reel 42 is connected to a spiral spring containinghousing 43. Spiral springs such as this are well known in the art andtherefore shown in FIG. 2 only by a spiraled dashed line 50. Spring 50is designed to urge rotational motion upon reel 42 in a direction so asto wind up the tape measure thereon. It may, therefore, be seen thattape measure 44 is always under tension, being stretched between the twoopposing reels 40 and 42 which are arranged to have generally balancedspring forces. Since, the forces are generally balanced there is notendency for the tape measure to roll either onto reel 42 or reel 40.The tape measure can be shifted, however, from one reel to another'byrotation of a crank 52 which is connected to reel 40 by means of a pairof pulleys 54 and 56 and a belt 58.

In operation, the operator of the machine simply places the desiredpiece of stock onto table 22 and clamps it to bracket 24. He thenrotates crank 26 so as to move sprocket 30 and chain 32 thus moving thecarriage assembly 12 along table surface 22 and moving the stock intothe desired position underneath the tool. Having determined the startingpoint the operator then rotates crank 52 so as to move tape measure 44until the zero point (or for that matter any other desired startingpoint) is visible through a magnifying plastic lens 60 which is insertedinto housing 28 immediately above tape measure 44. The zero mark isaligned with a suitable cross hair marker 62 which can be drawn ormounted on the bottom of lens 60 as desired. Idler roller 47 insuresthat tape measure 44 passes immediately underneath magnifying lens 60.With the tape measure in the zero position the operator locks the tapemeasure to carriage assembly 12 by activating an electric switch 64which is connected by a flexible cord 66 to an electromagthe stock ismoved. If the stock should be moved l6 inches, the operator need onlyactivate the switch locking the tape in place and operate crank 26 until16 inches of the tape measure has gone past the viewing window 60. Hethen locks the carriage in place through the use of brake 38 andactivates the tool to perform its function. He can then either releasebrake 38 and continue to move the stock an additional predetermineddistance or he can release electromagnet 68 and return the tape measureto the zero position so as to repeat the process. Since all the cranks,the switch and the viewing window are provided in one housing 28 it isclear that the operator need never move from his position near the toolnor will he require the services of someone else to help measure thestock. Hence, it may be seen that all the objectives of my inventionhave been accomplished.

I claim:

I. A work positioner for indicating the amount of movement of a piece ofstock relative to a tool comprising in combination:

- means for moving the stock relative to the tool;

first reel means mounted to move WITH SAlD stock;

second reel means fixedly mounted relative to said tool;

a graduated measuring tape extending between and wound onto both of saidfirst and second reel means, said first and second reel means havingfirst and second spring means connected thereto so as to urge thewinding of said tape onto both reel means in balanced opposition;

first crank means for winding and unwinding said second reel means; andclamping means operable to to clamp said tape so as to I move with saidstock.

2. The apparatus of claim 1 including magnifying means positioned topermit easier viewing of said tape.

3. The apparatus of claim 1 in which said clamping means comprises anelectromagnetic coil positioned to attract a metal block into contactwith said tape.

4. The apparatus of claim 1 in which said means for moving comprises asecond crank means mounted on a frame which is stationary relative tosaid tool and connected to move a stock engaging carriage upon which ismounted said first reel means.

5. The apparatus of claim 4 in which said clamping means comprises anelectromagnetic coil positioned on said carriage adjacent said tape andoperable to attract a metal block into locking contact with said tape.

6. The apparatus of claim 5 including a magnifying lens on saidstationary frame in position to allow a magnified view of said tape.

7. The apparatus of claim 6 in which said first and second crank meanscomprise hand cranks connected respectively to move said second reelmeans and said carriage.

8. The apparatus of claim 7 in which said electromagnetic coil isactivated by a switch on said stationary frame.

9. The apparatus of claim 8 including a first housing shroud about saidcarriage and containing said first reel means and said electromagneticcoil and a second housing shroud about said second reel and said crankmeans.

10. The apparatus of claim 9 including at least one idler wheel in saidsecond housing shroud to guide said tape past said magnifying lens whichlens is positioned in the wall of said second housing shroud.

1. A work positioner for indicating the amount of movement of a piece ofstock relative to a tool comprising in combination: means for moving thestock relative to the tool; first reel means mounted to move WITH SAIDstock; second reel means fixedly mounted relative to said tool; agraduated measuring tape extending between and wound onto both of saidfirst and second reel means, said first and second reel means havingfirst and second spring means connected thereto so as to urge thewinding of said tape onto both reel means in balanced opposition; firstcrank means for winding and unwinding said second reel means; andclamping means operable to to clamp said tape so as to move with saidstock.
 2. The apparatus of claim 1 including magnifying means positionedto permit easier viewing of said tape.
 3. The apparatus of claim 1 inwhich said clamping means comprises an electromagnetic coil positionedto attract a metal block into contact with said tape.
 4. The apparatusof claim 1 in which said means for moving comprises a second crank meansmounted on a frame which is stationary relative to said tool andconnected to move a stock engaging carriage upon which is mounted saidfirst reel means.
 5. The apparatus of claim 4 in which said clampingmeans comprises an electromagnetic coil positioned on said carriageadjacent said tape and operable to attract a metal block into lockingcontact with said tape.
 6. The apparatus of claim 5 including amagnifying lens on said stationary frame in position to allow amagnified view of said tape.
 7. The apparatus of claim 6 in which saidfirst and second crank means comprise hand cranks connected respectivelyto move said second reel means and said carriage.
 8. The apparatus ofclaim 7 in which said electromagnetic coil is activated by a switch onsaid stationary frame.
 9. The apparatus of claim 8 including a firsthousing shroud about said carriage and containing said first reel meansand said electromagnetic coil and a second housing shroud about saidsecond reel and said crank means.
 10. The apparatus of claim 9 includingat least one idler wheel in said second housing shroud to guide saidtape past said magnifying lens which lens is positioned in the wall ofsaid second housing shroud.